Arrangement for supporting mortar shell into barrel

ABSTRACT

The invention relates to an arrangement for supporting a mortar shell into the barrel of a mortar weapon by using a separate support piece fixed to the tail of the mortar shell. In the arrangement the support piece is attached to the tail of the mortar shell with a mechanical joint provided by a separate connecting element ( 7 ), the connecting element being manufactured of such material and constructed in such a way that it fractures when the charge of the mortar shell is fired, allowing the mortar shell ( 1 ) to detach from the support piece ( 8 ).

FIELD OF THE INVENTION

The invention relates to an arrangement for supporting a mortar shell inthe barrel of a breech-loading mortar weapon, said arrangementcomprising a support piece, with a rim flange, to be attached to thetail of the mortar shell.

BACKGROUND

A problem with mortars used on different armored self-propelled chassisconcerns the ability of the device to defend itself. If a heavy mortaris mounted on a chassis, it is not usually easy to mount on itsufficiently heavy artillery weapons for defense purposes. Lighterautomatic weapons, on the other hand, are not always sufficient againstantitank equipment or other artillery at a longer distance. In somecases it would be necessary to have the possibility to fire asmooth-bore mortar also horizontally with direct fire, which is notnormally possible. Any movement of the shell in the barrel can alsocause the shell not to go off when needed. One solution to this problemis proposed in the U.S. Pat. No. 5,503,080, in which a separate guidingand attachment element is used in the tail of a mortar shell. Saidsolution includes a separate guiding element furnished with groovesdimensioned according to the tail of the shell, the tail being pushedinto the grooves in such a way it is attached to the guiding elementwith a friction joint. A problem with this solution is that thefastening of the support piece is not reliable during handling, theoperational reliability of the shell being thus insufficient. Theapplication of said solution also requires very precise measures of thetail of the shell and its support piece, in order for the shell tofunction at least somewhat reliably.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an arrangement whichenables a mortar shell to be held securely and reliably in a correctposition in a barrel of a breech-loading mortar weapon and ensures itsreliable and secure operation under all circumstances.

An arrangement of the invention is characterized in that saidarrangement comprises, between a support piece and the tail of a mortarshell, a connecting element providing a mechanical joint, which enablesthe support piece to be attached to the tail of the mortar shell, andthat the support piece includes a firing member, with which the actualprimer can be fired to discharge the mortar shell.

An essential idea of the invention is that the support piece is arrangedto the shell with a mechanical joint, such as a thread or the like,provided by a separate connecting element, which is of such material andstructure that when the mortar shell is fired, the connecting elementbetween the mortar shell and the support piece fractures. Anotheressential idea of the invention is that the support piece comprises afiring member, which transfers the firing of the weapon to the primer ofthe mortar shell.

An advantage of the invention is that after the support piece isconnected to the mortar shell, the joint between them is firm and holdsthe mortar shell reliably and securely in place in a correct position inthe barrel of the weapon, irrespective of the position of the barrel.Another advantage of the invention is that it allows using existingmortar shells without changes made to the mortar shell itself or to thecharging system. A further advantage of the invention is that thesupport piece is light and inexpensive. One more advantage of theinvention is its convenience of use in sliding breech lock wedge typebased solutions, in which the sealing and the firing of the mortar shellwould be problematic.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in greater detail with reference to theattached drawings, in which

FIG. 1 is a schematic view of an arrangement of the invention arrangedto a mortar shell and

FIGS. 2a-2 c are schematic, enlarged and partly cross-sectional views ofembodiments of an arrangement of the invention.

DETAILED DESCRIPTION

FIG. 1 is a schematic view of a mortar shell 1, known per se, comprisinga tail tube 2. At the rear end of the tail tube 2 there are fins 3,which guide the flight of the mortar shell. Their structure andconstruction are commonly known per se, so their previously knownembodiments need not be clarified in greater detail.

FIG. 2a shows a schematic, partly cross-sectional view of an embodimentof an arrangement of the invention. The tail tube 2 of the mortar shellcontains a propelling charge 4, which is used to expel the mortar shellfrom the barrel. For the firing of the propelling charge 4, a primer 5is arranged at the end of the tail tube 2 with a separate attachmentpiece 6 provided with threads. Normally, when a mortar is used to firemortar shells, the firing pin of the mortar strikes a primer 5 whichfires the propelling charge 4, thereby expelling the mortar shell fromthe barrel.

The Figure also shows a separate connecting element 7 with a thin flange7 a. The flange 7 a is located between the tail tube 2 and theattachment piece 6 in such a way that the attachment piece 6 attachesthe connecting element 7 to the mortar shell. The connecting element 7,in turn, has a thread 7 b, to which a separate support piece 8 isattached with a corresponding thread 8 a. The support piece 8 resemblesa short case end with a cylinder part extending around the fins 3 insuch a way that when the mortar shell is in the barrel of the weapon, itis in a substantially direct and central position parallel to thebarrel. The support piece also has a rim flange 8 b, which sets in agroove at the rear part of the weapon's barrel, holding the mortar shellin a correct position in the barrel, irrespective of the position of thebarrel, at the same time as the cylinder part seals the barrel. Thesupport piece 8 further includes a firing member 9, which in thisembodiment comprises an intermediate firing pin 9 a and an electricalprimer 9 b. The intermediate firing pin 9 a is normally kept in itsplace by a separate closing plate or a similar locking member 10, whichprevents the intermediate firing pin from moving until the electricalprimer is fired, after which it yields so as to enable the intermediatefiring pin to strike the primer 5 of the mortar shell and thereby firethe propelling charge 4 of the mortar shell. As the propelling charge ofthe mortar shell is fired, the flange 7 a of the connecting element 7fractures and comes off the connecting element and the mortar shell isexpelled from the barrel while the support piece 8 and a major part ofthe connecting element 7 stay in place. Instead of an electrical primer,it is naturally possible to use a conventional primer, which theweapon's firing pin strikes upon discharging, thereby firing, with theintermediate firing pin 9 a, the primer 5 of the mortar shell.

FIG. 2b shows another embodiment of an arrangement of the invention. Inthis embodiment the attachment piece 6 has a thread 6 a on its outersurface. The support piece 8 correspondingly has on its outer surface athread 8 a with preferably the same dimensions. The connecting element 7in this case is a sleeve-type element connecting the attachment piece 6and the support piece 8 to each other. The connecting element 7 is inthis case of such material that its threads 7 b at the primer end of theattachment piece 6 fracture and come off or are deformed in such a waythat the mortar shell is easily expelled when the charge is fired. Ifdesired, the connecting element 7 can also be provided with a weakenedsection 11, where the connecting element 7 can fracture. This can alsobe used in a solution according to FIG. 1 and in other arrangements ofthe invention possibly implemented.

FIG. 2c shows a third embodiment of the invention, in which firing isnot achieved using a separate primer. The firing member in this caseonly comprises the mechanical firing pin 9 a without a separate primer,and the locking member 10 ensures that the pin is kept in place so thatonly when the firing pin of the weapon strikes the head of theintermediate firing pin 9 a, it strikes the primer of the mortar shell,firing thus the charge of the mortar shell. The rear end of theintermediate firing pin 9 a is in this case locked, e.g. with a lockingring 12 located in a groove behind the firing pin 9 a and preventing itfrom falling from its place.

The above description and the drawings of the invention only representan example of it, the invention not being restricted to it. Connectingelements can be shaped in different ways and manufactured of differentmaterials, such as plastics, different composition metals, etc. Anessential feature is that the support piece is attached to the mortarshell with a mechanical joint, preferably with a thread, in such a waythat they are kept firmly together before the firing. It is alsoessential that as the mortar shell charge is fired, a part of theattachment piece fractures or is deformed in such a way that the mortarshell is detached from the support piece. Yet another essential featureis that the connecting element is strong enough to keep the supportpiece sufficiently firmly attached to the mortar shell during otherhandling of the mortar shell.

What is claimed is:
 1. Apparatus for supporting a mortar shell in abarrel of a breech-loading mortar weapon, said apparatus comprising: asupport piece attachable to an end of the barrel of the breech-loadingmortar to close said end, the mortar shell having a tail end with a tailtube including an attachment piece containing a primer to fire apropellant charge in the mortar shell, said attachment piece beingattached at an end of the tail tube, said support piece including afiring mechanism for firing the primer in the mortar shell and therebythe propellant charge to fire the mortar shell from the barrel, and anattachment arrangement attachable to the attachment piece in the mortarshell and to the support piece in the barrel to enable the tail end ofthe mortar shell to be securely supported in the barrel, said attachmentarrangement including a separable portion which separates when thepropellant charge is fired and the mortar shell is fired from thebarrel, said attachment arrangement being selectively attachable to themortar shell to enable the mortar shell to be selectively used with orwithout the support piece and the attachment arrangement.
 2. Theapparatus as claimed in claim 1, wherein said attachment arrangement isthreadably engageable with said support piece.
 3. The apparatus asclaimed in claim 1, wherein said attachment arrangement comprises aconnecting element threadably engaged with said attachment piece.
 4. Theapparatus as claimed in claim 3, wherein said connecting elementincludes a region which is dimensioned to fracture when the mortar shellis fired.
 5. The apparatus as claimed in claim 4, wherein said region insaid connecting element is located so that when said region is fractureda part of the connecting element remains connected to the attachmentpiece and another part remains connected to said support piece.
 6. Theapparatus as claimed in claim 5, wherein said part of the connectingelement which remains connected to the attachment piece comprises a thinflange secured between the attachment piece and the end of the tail tubeof the mortar shell.
 7. The apparatus as claimed in claim 3, whereinsaid connecting element comprises a sleeve threadably attached to saidattachment piece and to said support piece.
 8. The apparatus as claimedin claim 7, wherein said sleeve has a weakened section which fractureswhen the mortar shell is fired.
 9. The apparatus as claimed in claim 7,wherein said sleeve is made of a material to fracture or be deformedwhere the sleeve is threadably attached upon firing of the mortar shell.10. The apparatus as claimed in claim 1, wherein said firing mechanismcomprises a separate intermediate firing pin; a closing member providedwith a space in which the intermediate firing pin is movably supportedto move to the primer in the mortar shell and fire the primer and aseparate locking member for preventing the intermediate firing pin frommoving towards the primer in the mortar shell, said locking memberyielding or fracturing from the impact of a force on the intermediatefiring pin allowing the intermediate firing pin to strike the primer.11. The apparatus as claimed in claim 10, wherein said firing mechanismfurther comprises means for moving said firing pin to strike the primer.